.\" Copyright (c) 2005 Robert N. M. Watson
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.Dd August 10, 2012
.Dt SCHED_ULE 4
.Os
.Sh NAME
.Nm sched_ule
.Nd ULE scheduler
.Sh SYNOPSIS
.Cd "options SCHED_ULE"
.Sh DESCRIPTION
The
.Nm
scheduler
provides a number of advanced scheduler
features not present in
.Xr sched_4bsd 4 ,
the traditional system scheduler.
These features address SMP and interactivity and include:
.Pp
.Bl -bullet -compact -offset indent
.It
Thread CPU affinity.
.It
CPU topology awareness, including for hyper-threading.
.It
Per-CPU run queues.
.It
Interactivity heuristics that detect interactive applications and schedules
them preferentially under high load.
.El
.Pp
The following sysctls are relevant to the operation of
.Nm :
.Bl -tag -width indent
.It Va kern.sched.name
This read-only sysctl reports the name of the active scheduler.
.It Va kern.sched.quantum
This read-write sysctl reports or sets the length of the quantum (in
micro-seconds) granted to a thread.
.El
.Sh SEE ALSO
.Xr sched_4bsd 4 ,
.Xr sysctl 8
.Sh HISTORY
The
.Nm
scheduler first appeared in
.Fx 5.1 .
.Sh AUTHORS
.An Jeff Roberson Aq Mt jeff@FreeBSD.org
